Bumping into Jesus

One of the things Christians should care about: our spiritual health and salvation / getting right with God. But do we understand salvation? Many people "bumped into Jesus," or had contact with him when he was in a crowd. Yet not all of them were changed nor saved just from this casual or accidental contact. But there was a woman who deeply believed Jesus could heal her and deliver her from sickness. She simply touched his robe and was healed. What was different?